For a while now it’s been hard to shake the image of virtual reality as something of a gimmick, and whilst this feeling persists to a large extent, there are nonetheless some fascinating new applications of it in the healthcare world.
For instance, I wrote recently about an interesting application of virtual reality to help patients rehabilitate after an injury. Immersive Rehab aim to help these people by offering both neurological and physical rehab in a virtual environment. Users perform the same kind of movements they would attempt in physical rehab, but they are grabbing and interacting with items virtually. The idea is that they trick the brain into thinking they are engaging with real objects, and thus make important gains in their mobility.
There has also been a deployment of VR to help give terminally ill patients a virtual trip down memory lane. Users are transported to a familiar location for them, whereby they can interact with family and friends.
Predicting falls
Continuing the trend, a recent study by the University of North Carolina at Chapel Hill and North Carolina State University examined the use of VR in reducing falls among the elderly. The team used a VR system to create the illusion of a loss of balance as participants walked on a treadmill. The researchers monitored how this shock to their sense of balance influenced their movement and understand the muscular response in our bodies.
“We were able to identify the muscles that orchestrate balance corrections during walking,” the team say. “We also learned how individual muscles are highly coordinated in preserving walking balance. These things provide an important roadmap for detecting balance impairments and the risk of future falls.”
Healthy adults usually balance via the mechanical ‘sensors’ we have in our feet and legs. The sense of proprioception that allows us to easily walk in the dark declines as we age, as well as in people who have neurodegenerative diseases, such as multiple sclerosis. For these people, visual cues become more important in retaining balance. The researchers attempted to disturb these visual cues via the VR.
“As each person walked, we added lateral oscillations to the video imagery, so that the visual environment made them feel as if they were swaying back and forth, or falling,” they say. “The participants know they aren’t really swaying, but their brains and muscles automatically try to correct their balance anyway.”
Capturing motion
The team used the kind of video technology typically seen in Hollywood animation studios to capture the motion of each participant. This level of detail allowed them to hone in on the specific muscle groups that control posture and foot placement as we attempt to regain a perceived loss of balance.
By monitoring our response to a loss of balance, the team gained important insights into the very mechanisms that allow us to maintain balance. The team also gained key reference measurements that they believe could be used in clinical procedures to detect balance problems before they result in an actual fall.
The team are conducted similar studies with elderly participants, and they hope to perform the same with multiple sclerosis sufferers to help determine customized detection procedures.
“We think there’s a big opportunity to use visual perturbations in a VR setting to reveal balance impairments that would not be detected in conventional testing or normal walking,” they say. “The key is to challenge balance during walking, to tease out those impairments that exist under the surface.”
Continuing the VR theme, the team also want to explore whether VR can be used as a physical therapy tool to help the balance-impaired to improve their balance and thus avoid falls. Their early work suggests this is possible, so it will be interesting to track their work going forward.
